This invention generally relates to hydraulic actuators and more particularly to a disk brake actuator as may be applied to aircraft type disk brake assemblies.
Disk brake assemblies of the type alluded to are conventionally full circle configurations which incorporate at least two piston actuators in a balanced arrangement about the circle and which operate to move a pressure plate into engagement with a disk brake stack comprised of alternating stationary and rotating disk elements. The prior art piston actuators conventionally employ a single piston which results in a linear relationship between the disk interface pressure and the brake system pressure as illustrated by the dashed line showing of FIG. 4. Also, and as illustrated in FIG. 5, these prior art actuators have a step-like displacement vs. pressure characteristic.
Accordingly, it is a purpose of this invention to provide an actuator which has a more gradual and changing linear relationship between the interface pressure and the system pressure as illustrated by the solid line showing in FIG. 4. Also, the invention provides a variable displacement vs. pressure characteristic as shown by the solid line portion of FIG. 5.